SACRAMENTO (AP) — Weeks after New York enacted the nation's toughest gun laws, California lawmakers said Thursday they want their state to do even more in response to recent mass shootings, particularly the Connecticut school massacre.

Democrats who control the state Legislature revealed 10 proposals that they said would make California the most restrictive state for possessing firearms.

They were joined at a Capitol news conference by San Francisco Mayor Ed Lee and Los Angeles Mayor Antonio Villaraigosa, along with several police chiefs.

"California has always been a leader on the issue of gun safety," Villaraigosa said. "New York has stepped up and stepped forward. California needs to answer the call."

Among the measures is one that would outlaw the future sale of semi-automatic rifles with detachable magazines. The restriction would prevent quick reloading by requiring bullets to be loaded one at a time.

Lawmakers also want to make some prohibitions apply to current gun owners, not just to people who buy weapons in the future.

Like New York, California also would require background checks for buying ammunition and would add to the list of prohibited weapons.

Those buying ammunition would have to pay a fee and undergo an initial background check by the state Department of Justice, similar to what is required now before buyers can purchase a weapon. Subsequent background checks would be done instantly by an ammunition seller checking the Justice Department's records.

The legislation also would ban possession of magazines holding more than 10 bullets, even by those who now own them legally. All weapons would have to be registered.

Sam Paredes, executive director of Gun Owners of California, promised that gun proponents will fight the measures in court if they become law.

"It strikes me as if these folks are playing some sort of game of one-upsmanship with New York at the expense of law-abiding citizens, and that's just unconscionable," he said about lawmakers.

Three bills have been introduced, with others to come before this month's deadline for submitting legislation.

The measures are the most stringent to date among numerous proposals introduced this year to strengthen California's firearm regulations.

Senate President Pro Tem Darrell Steinberg said he is confident Democrats can use their majorities in the Assembly and Senate to send the measures to Democratic Gov. Jerry Brown this year.

Brown has declined to comment on weapons legislation before it reaches him.

Steinberg said the measures are designed to close numerous loopholes that gun manufacturers have exploited to get around California's existing restrictions.

Those measures had been the strongest in the nation until Gov. Andrew Cuomo signed New York's new law last month.

Other proposed measures in California would ban so-called "bullet buttons" that can be used to quickly detach and reload magazines in semi-automatic rifles, and update the legal definition of shotguns to prohibit a new version that can rapidly fire shotgun shells and .45-caliber ammunition.

The state also would restrict the lending of guns to keep weapons from felons, mentally ill people and others who are prohibited from ownership.